When Intent is received in Xamarin, ensure that only one instance is running at any given time

The Xamarin App sends and receives requests to the "central microservice" every 5 seconds using a timer. We can do an "action" in two ways: using intent from another app or scanning a QR code from a web app. Our app sends a request to the "central microservice" when scanning a QR Code or receiving an Intent, and receives a request from the "central microservice" after "5" seconds.

When scanning a QR code, the "central microservice" sends a single request per call. However, while using Intent from another app, you may receive an additional request. Apps are executing in two instances on Intent.

In the AndroidManifest.xml file, I tried adding android:launchMode="singleInstance" and android:launchMode="singleTask".

In MainActivity.cs, I inserted LaunchMode = LaunchMode.SingleTask and LaunchMode = LaunchMode.SingleInstance.

In Another App (the Intent comes from), I inserted intent.addFlags(Intent.FLAG ACTIVITY REORDER TO FRONT).

Both Apps are still active (can be seen by minimizing the app). How can I ensure that only one instance of the app is running at any given time when the Intent is being received?

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